My first interaction with a multi-cultural environment was in high-school (more like culture-shock). First year was extremely rough because I didn't understand the 'culture' or even why 'high-school' was such a big deal! I guess, back home I was being brought up on a very sheltered turf. Anyways, eventually I caught up and by the time I was in college (which was 100 times more culturally diverse than high school) I was a little more comfortable with people from different backgrounds!
Now, looking back, I can honestly say that I never formed any preconceived notions about any nationality or culture. I took my sweet time before I made-up my opinion about anyone (or anything) and mostly based it on hard facts. But I was never (I know - 'Never say Never' - But I am saying never) stereotypical about it!
I personally think we should be very careful about what we say and how we think. It's our words and thoughts that is forming our society today more than actions and education (considering we have very well-educated terrorists nowadays). Besides we all know everyone is different. It's simply unfair to label countries and religions ( ... then we wonder why certain people are so bitter?!?!).
Like my dad says, we should be extremely patient with people; you never know who might surprise you. Everyone deserves a 'benefit of doubt'!
Ever heard ... Innocent until proven guilty?!?!